Continuous pavement cutter

ABSTRACT

An apparatus used in conjunction with the ripper bar of a prime mover for removing a section of overlaying asphaltic pavement preparatory to digging a trench or repairing a street which consists of a cutting member having a leading edge which slices a thickness of pavement from the subgrade, a side edge in combination with a pavement engaging wheel which cuts a side of the pavement; the cutting member being curved upwardly and rearwardly to lift and break the pavement.

ll1l3,592,509

United States Patent [72] Inventor VernonR.Soderlund 2,768,794 10/1956 Putnam..,..............,.... 6514 Lucas Ave., Oakland, Calif. 9461i 2,878,002 3/1959 Haley 12/1969 Soderlund....................

[54] CONTINUOUS PAVEMENT CUTTER PATENTED Llum 319m SHEETl l 0F 6 INVENTOR Vernon R. Soderlund @fly Owl.

Attorneys PATENTFHJUMBIQN 3,592,509

INVENTOIL IVernon R. Soderlund 26 Aforne ys SHEET 3 UF 6 PATENTEU JUL 1 31971 INVENTOR Vernon R. Soderlund BY p @fa-MO .XV

Attorneys www JUL i a um SHEET u UF 6 INVENTOR Vernon R. Soderlund Attorneys PATENTEU um 3 Isn 59? 50g snm 5 nr 6 mvENToR BY Vernon R. Soderlund Attorneys PATENEU JUL 1 3 :91|

SHEET 8 UF 6 INVENTOIL BY Vernon R. Soderlund Attorneys The invention is primarily used in cutting a'sphaltic concrete pavement preparatory to digging trenches in streets for undergrounding pipes, cables and various utilities. It is also used in removing old pavement prior to street repair. It is far superior to prior devices in common use for cutting pavement strips which consist of drop chisels mounted on vehicles which successively lift and drop the chisels as the machines inch forward intermittently,

The only continuous pavement lifter known to this applicant is a device set forth in my. patent application filed Dec. 13, |967 Ser. No. 690,152 and now Pat. No. 3,486,795 entitled PAVEMENT LIFTER.

SUMMARY OF THE INVENTION This invention contains many of the improvements over drop chisels set forth in my above-named patent application. In addition, this invention is an improvement over the apparatus set forth in my prior application in that it is a simpler less expensive unit and trenches of variable width may be cut, the apparatus may be connected to either a ripper bar which is raised and lowered or tilted or by a parallelogram arrangement; the cut is cleaner and pavements of greater depth may be cut. The gist of the invention is the discovery that the use of a cutting member in combination with a wheel can continuously make a clean cut through asphalt pavement.

An object of the present invention is to provide an apparatus which can cut asphalt pavements whichis inexpensive, yet faster and more versatile than previous devices.

Another object is to provide a cutter which is adjustable so that pavements of different thickness may be cut.

A further object is to provide a cutter which has a self-starting tip so that the hand labor of starting a hole for the cutter may be eliminated.

Still another object is to provide a device which will cut a slot in pavement with a minimum of disturbance or breakage to both sides of the cut.

A still further object is to providea device which can form a cut in the pavement and then be moved to a new position to form a device for breaking pavement so that it can be removed from the roadbed in manageable pieces.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view of a pair of the devices connected to a prime mover designated B and C.

FIG. 2 is a front elevation view of unit B ofthe device of the present invention with the direction of travel being toward the viewer.

FIG. 3 is a side cross-sectional view of the device taken substantially along line 3-3 on FIG. 2;.the phantom lines showing a different position of the device' to make a thinner slice of pavement.

FIG. 4 is a rear elevation view'of the device indicated as unit B constructed in accordance with the present invention with the direction of travel of the device away from the viewer.

FIG. 5 is a cross sectional view of the device shown in FIG. 3 taken substantially along the line 5-5.

FIG. 6 is a side elevation view ofan alternate form of the invention.

FIG. 7 is a rear elevation view ofthe device shown in FIG. 6.

FIG. 8 is a side elevation view of another alternate form of the invention. l

FIG. 9 is a rear elevation view of the device shown in FIG. 8.

FIG. I is a plan view ofthe deviceshown in FIG. 8.

FIG. ll is a side elevation view of. still another form of the invention.V n

FIG. 12 is a rear elevation of the device shown in FIG. I l.

FIG. 13 is a plan view ofthe device shown in FIG. l1. Y

l FIG. 14 is a side elevation view of another form of the invention.

FIG. l5 is a rear elevation view of the device shown in FIG. 14.

FIG. 16 is a plan view of the device shown in FIG. 14.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention consists briefly of a frame adapted for attachment to a prime mover A such as a crawler tractor, heavy truck or pneumatic tired earthmover. Attached to the frame is a ground engaging member l which could be a skid but is here shown as a wheel which applies surface pressure against the ground over a substantial enough area lateral to the direction of movement of the device to prevent uplifting-of the pavement immediately adjacent the trench being cut. Also attached to the frame is a compound curved blade 2 mounted on the frame having a forward elongated edge 3 positioned at a lower elevation relative to the'ground engaging member for slicing a thickness of pavement from the subgrade; a first end 4 of the forward edge being substantially in alignment with one edge of the ground engaging member for performing an axial cut in the pavement in cooperation with the ground engaging member; and the second end 5 being spaced laterally away from the ground engaging member. The blade extends rearwardly and upwardly from the forward edge with the portion of the blade 7 extending behind the first end rising more rapidly and to a relatively greater elevation than the portion 8 behind the second end thereby'causing the pavement to be i lifted and curled in a direction away from the ground engaging member as the apparatus is moved forwardly.

The forward edge of the blade should be hardened or provided with a replaceable cutting edge. All other portions of the device may be constructed from standard heavy construction materials.

Although the device may be used as a single unit as forexample where the trench occurs at one edge of the` pavement, primarily the device will be used in pairs as shown in FIG. l where the first and second units are designated B and C. The inner edges of the ground engaging members define the outer limits of the width of the trench.,V

An important feature of the present invention is the ability to cut trenches of different widths with the same basic device. Accordingly, the units are demountably and slidably con*- nected to an elevating member on the prime mover such as the ripper bar 9 on crawler tractors. The particular attachment depends upon the configuration of the ripper bar but some frames may be attached by a plurality of bolts 11 connecting an upper plate l2 with a lower plate member I3.

In order to apply the maximum pressure to the ground with the least stress on the equipment it is desirable to mount the wheel substantially beneath the ripper bar as shown in FIG. l.

Another feature of the present invention is the fact that it is an attachment rather than a motorized unit .having a single purpose such as the present. chisel mounted pavement breakers. The devices may be detached from the prime mover and rippers, blades and other attachments can be affixed in their place.

The frame consists of at least one and preferably a pair of horizontal members 16 and l7,connected to the lower plate member I3. A vertical member 18, which is preferably a portion of horizontal member 16, and which is at least integral with the aforementioned horizontal member extends downwardly from the trailing end of the horizontal member rearwardly of the wheel. The blade is connected to the vertical member. A great deal of lateral thrust is placed on the vertical member and it should be suitably braced by members 19. Due to the width of the ground wheel, the vertical member must be bent toward the wheel as shown in FIGS. 2 and 4. Connection to the blade may be made in various ways and is here shown with a portion 2l in front of the blade and a portion 224 behind the blade.

The device is constructed withva wheel carrying member 23, pivotally attached to the leading end 24 of the horizontal member by pin 26.`The wheel is attached to the wheel carrying memberby axle 27.

Depth adjustment is effected by a structure consisting of an adjustment member 28 connected to the trailing end 29 of the wheel carrying member in an upright manner. The adjustment member is formed with a plurality of spaced openings 3l. A pin member 32 is dimensioned for registration in the openings for selectively adjusting the depth of the blade in relation to the bottom edge of the wheel for determining the thickness of the slice of the pavement to be cut and lifted.

It is desirable, if not in fact essential that the depth of the blade be governed by the elevation of the prime mover rather than the ground wheel. Accordingly, the device includes means for permitting the ground wheel to raise and lower within a limited range without affecting the elevation of the blade. To accomplish the foregoing, a spring 33 coaxially surrounds the adjustment member. The upper end of the spring is retained by an upper fixed spring retainer plate 34 and annular ring 37 connected to a pair of channel members 3S and 36. The lower end of the spring is retained by a lower floating spring retainer means consisting of a cylindrical member 38 mounted coaxially within the spring and surrounding the adjustable member and having an opening 39 therethrough for receiving the pin and a horizontal member 41 engaging the lower end of the spring. To prevent shearing of the pin, sleeves 42 and 43 are inserted between the pin and the upright channels and the cylindrical member. The channels are formed with elongated vertically extending slots 44 and 45 at the point where the pin is inserted therethrough. The amount of wheel springing is limited by the length of the slots.

To reduce the power necessary to slice the pavement and permit easier starts, the first end of the forward edge of the blade substantially leads the second end thus presenting a4 blunt point 47.

As shown in FIGS. 2 and 3, the upper edge of the blade adjacent the ground engaging member is spaced laterally away from the ground engaging member and a portion of the upper end of the blade is positioned above the upper surface of the pavement to be lifted.

ln operation, units B and C are attached to the ripper bar of a tractor. First, the depth of the pavement to be removed from the subgrade is determined and the blade depth is then set as follows. Since the construction of both B and C units is identical except for the location of the blade in reference to the wheel, only the operation of one unit will be described.

The adjusting pin is removed and the wheel and adjustment bar are moved upwardly or downwardly until the desired spacing is reached. The pin is then inserted through the opening in the channel member, through the cylindrical portion of the lower spring retainer member and through the other channel. The ripper bar on the prime mover is lowered until the blade contacts the surface. The prime mover is moved forwardly and the blade continues to be lowered until the ground engaging member contacts the surface of the pavement. At this point the prime mover is in position to slice, cut and lift the pavement from the trench area.

As the prime mover moves forward, the leading edge of the blade slices the material between the pavement and the subgrade. The blade is previously set just below the level of the pavement. As the blade moves forward, the pavement is lifted. As set forth above, the edge of the blade adjacent'the ground engaging member rises at a greater rate than the other edge so that the pavement tears away from the outer edges ofthe trench. Since the ground engaging wheel is applying pressure to the sides of the trench, the cutting or tearing of the pavement occurs on a plane at the inner edge of the wheel designated by the number l in FIGS. 2 and 4.

Pavement from a relatively wide trench can be removed in this manner since even though the pavement in the center portion ofthe trench may not be broken up like the sides, yet it is relatively' easy to remove by means of a backhoe or other mechanical device since there is little adhesion between the pavement and the subgrade. As long as the sides of the trench have been cut away from the larger body ofpavement the relatively unbroken center portions ofthe pavement can be easily removed.

Since the blade is set at an angle to the plane of the pavement, the leading edge of the blade will automatically follow the lower edge of the pavement should there be some variation in the thickness of the pavement. This is made possible by permitting the ground engaging member to raise and lower against the action of a spring. Thus, if the blade suddenly goes to a lower elevation due to an increasein the thickness of the pavement, the rear of the prime mover will dip down and the wheel will move upwardly and compress the spring. As the blade moves upwardly after passing under the thickened portion, the wheel will again be lowered by the spring which has been compressed. V

The operation of the device described above and the alternate forms to be described is basically different from my invention described in application, Ser. No. 690,152. The operation of the device described in the previous application is very similar to the action of tearing a piece of paper by holding a .straight edge on the paper and lifting and pulling the paper away from the straight edge. The operation of the devices described in the present application is similar to the action of a pair of shears.

Referring to the alternate form of the device as shown in FIGS. 6 and 7, the device consists briefly ofa pavement engaging member 6l for applying a force to the pavement 62 to prevent uplifting; a cutting member 63 having a leading edge 64 spaced below and offset from the pavement engaging surface of the pavement engaging member for severing a thickness of pavement from the subgrade; the cutting member having a cutting edge 66 immediately adjacent an edge 67 of the pavement engaging member extending upwardly from the leading edge so as to coact with the pavement engaging member in forming a clean side cut 68 in the pavement; and a frame 69 to which the pavement engaging member and cutting member are attached, the frame having means such as openings 71 adapted for connection to a prime mover such as the one shown in FIG. l for continuously moving the device through asphaltic pavement for forming a linear cut therethrough.

The important difference between the device shown in FIG. 6 and the device shown in the previously described figures, is the fact that the cutting member is narrower, being in the order of l thick. Further, there is no compound curve of the cutting member. As before, the cutting member is on an incline. The leading edge is in front of the portion of the wheel 73 contacting the pavement.

Preferably, the ground engaging member is a wheel having a tread about 8 inches in width. The tread width may vary as the thickness and the hardness of pavements to be cut. The wheel is here connected to an axle 74 which is journaled between outer plates 76 and 77. Washers 78 and 79 are mounted on the axle between the wheel and the plates. Cross plates 8l and 82 join the outer plates and form the basic frame.

The cutting member may be formed integrally with the attachment means as shown in FIGS. 6 and 7. As here shown the single member is connected to the frame as by welds 83 and is formed with an offset 84 so as to achieve the greatest structural rigidity and to ensure proper placement of the cutting edge in relation to the ground engaging wheel as well as to permit portions of the severed pavement 85 to move without binding past the frame.

One of the difficulties in any device which is designed for continuous operation is the problem of designing it so that it is self-starting. Earlier forms of the invention would merely skid along the upper surface of the pavement and it required a starter hole in order to get the leading edge down through the pavement so that it could accomplish the work intended. The solution was a starting point 86 connected to the cutting member and extending downwardly and forwardly of the leading edge so that the pavement would be punctured and the leading edge would drop to the selected elevation for performing its operation of severing the pavement from the `subgrade 80. Notice that the angle of the starting edge, in relation to the plane ofthe pavement, is steeper than the angle of the cutting edge. The cutting edge and leading edge as here defined may be separate pieces or be integral with the main body of the cutting member. It has been found that the cutting edge wears quickly and it is desirable to attach a hardened piece of steel 87.

An alternate form of the device shown in FIGS. 6 and 7 is shown in FIGS. 8, 9, and 10; and since the basic operation is identical except for the feature of depth control, only the parts necessary to accomplish the depth control will be specifically described. Briefly, the ground engaging mem ber 61' mounted on axle 74 is pivotally mounted on the frame at pin 88. Connection means, here shown as openings 89 formed in a frame 90 connected to the frame which journals the ground engaging wheel, register with opening 91 in the cutting member. A pin 92 is inserted through the openings to place the starting point 86 and leading edge 64' at different elevations in relation to the ground engaging wheel. Vertical adjustment permits pavements of different thickness to be more easily severed from the subgrade.

As shown, the cutting edge 66 and hardened steel member 87 are supported by a member 63' which is formed with a double offset 93 to permit the severed pavement 85 to move past the frame without binding. The solid lines show the ground engaging wheel in contact with the pavement 62' for removing pavement from subgrade 80'. The phantom lines show the ground engaging wheel in contact with the subgrade 62 (a) when the wheel is placed in a shallow cut adjustment. A frame 69 has openings 71' adapted for attachment to a prime mover.

Another form of the invention is shown in FIG. 11, l2 and 13. The purpose of this device is to make a slot in the pavement with two relatively clean cut sidewalls. The device consists briefly of a first pavement engaging member 61" and a second pavement engaging member 96 spaced therefrom with just sufficient distance to place the cutting member 63" therebetween. A leading edge 64" is spaced below and offset from the pavement engaging surfaces 73" and 73" (a) of the pavement engaging wheels for severing a narrow strip of pavement 85" from the subgrade 80". The cutting member has cutting edges 66" and 66" (a) which extend upwardly from the leading edge so as to coact with the pavement engaging members in forming a pair of clean side cuts 68" and 68" (a) in the pavement. The pavement engaging members and cutting member are attached to a frame 69" which in turn is connected to an upright member 97 which is adapted for connection to a portion of the prime mover 98. The ground engaging members are connected to axle 74" journaled in side plate members 76" and 77". One ofthe problems encountered with the slotting device is the tendency of the pavement to ride around the wheels. This problem was solved by placing a guide member 99 extending between the wheels and extending from the axle, upwardly and rearwardly. The member is here shown with curved portion 101 slidably connected to the axle and fastened to the frame by a bracket 102.

Two additional alternate forms of the invention are shown in FIGS. 14, and 16. The first form of the invention is shown generally by solid lines whereas the second form is shown by the dotted lines in addition to a portion of the solid lines, In brief the first form consists of the combination shown in FIGS. 6 and 7 with the addition of an outrigger wheel to limit the extent of pavement breakage. Specifically, the invention consists of a pavement engaging member 61"' for applying a force to the pavement 62"' to prevent uplifting; a cutting member 63" having a leading edge 64" spaced below and offset from the pavement engaging surface 73" of the pavement engaging member for severing a thickness of pavement from the subgrade 80"'; the cutting member having a cutting edge 66 immediately adjacent an edge 67" of the pavement engaging member extending upwardly from the leading edge so as to coact with the pavement engaging member in forming a clean side cut 68" in the pavement; and a frame 69"' to which the pavement engaging member and cutting member are attached, the frame having means such as opening 71"' adapted for connection to a prime mover such as the one shown in FIG. 1 for continuously moving the device through asphaltic pavement for forming a linear cut therethrough. Attached to the frame is an outrigger ground engaging member 106 spaced laterally from the cutting member opposite the placement of the first named pavement engaging member for limiting the lateral extent of the pavement breakage. The Outrigger wheel'is mounted on an axle 107 journaled in bracket members 108 and 109. As in the drawing of FIG. 15, the uplifted pavement breaks at approximately the point beneath the Outrigger wheel.

The second form of the invention shown in FIGS. 14-16 performs a somewhat different, though closely related, function; namely, breaking the pavement into smaller pieces after the sides of the trench have been cut. Basically the pavement breaking function is performed by the use of a single cutter member spaced approximately equidistant between two Outrigger wheels. Specifically this form of the invention is shown with the ground engaging wheel 61"' pivotally swung to the position shown by the dotted lines in FIGS. 15 and 16. Thus, as can be seen, the device has the dual capacity of forming a clean edge cut between the pavement to be removed and the pavement that remains and also, by a slight adjustment, can be used to break up the pavement so that it can be easily handled by the equipment normally used in street repair. To accomplish this function, the frame is extended by plates 111 and 112 which rotatably receive pivot pin 113. The pivoting frame 114 may be locked in the two positions by placing a pin 116 through registration holes 117, 121 and 118. To lock the device in the breaking mode, the pivoting frame is rotated about its pivot until registration opening 121 in the pivot frame registers with openings 123 and 124 in the frame. The locking pin is then placed in the later openings. In the breaking mode, the cutter lifts the pavement at the cutter and the lateral breaking extends generally to the outrigger wheel and to the pavement engaging wheel as shown in phantom line in FIG. 15. The pavement engaging wheel is mounted on axle 74" journaled in openings in frame members 126 and 127 of the pivoting frame 114. Brace members 131 and 132 are connected to the cutting member to stabilize it.

Referring again to FIGS. 11-13, it has been found that this device when modified slightly by increasing the tread width of the ground engaging wheels and increasing the wheel diameter can be used to dig trenches in soil not covered by pavement such as golf courses. The advantage of the machine of the present invention is that a narrow trench with cleanly cut sides can be made with a minimum disturbance to the turf adjoining the trench. The device can cut trenches of about 11/2 feet to 2 feet in depth and about 8 inches in width. These trenches are especially useful for laying french drains either pipe or gravel. The tread width should be about 7 or 8 inches and the wheel diameter about l foot to 2 feet. The dia.....ter of the wheel generally should be equal to or greater than the depth ofthe cut. Because of the reduced power requirements in digging trenches in soil, the average rubber tired back hoe tractor is generally sufficient.

In order to prevent the uplifted soil from falling back into the trench it is suggested that a pan be skidded behind the device to catch the soil. A low-wheeled cart can also be used. When the skid pan or cart is loaded with soil it can be dumped in a convenient place to the side of the golf course or lawn for later covering the 8 inch drain perforated pipe. By taking the soil away from the trench the labor of raking the loose soil out of the turf is eliminated and the excess soil is immediately disposed of.

l claim:

1. A pavement slicer, cutter and lifter comprising:

a. a frame adapted for attachment to a prime mover;

b. a ground engaging member mounted on said frame adapted for applying surface pressure against said ground over a substantially sufficient area to prevent pavement uplift lateral to the direction of movement of said device;

and

c. a compound curved blade mounted on said frame having a forward elongated edge positioned at a lower elevation relative to said ground engaging member for slicing a thickness of pavement from the subgrade, a first end of ing mem beiA is spaced laterally away from said ground engaging member and a portion of said upper end of said blade is positioned above the upper surface of said pavement to be lifted.

l0. A pavement cutting device comprising: a. a pavement engaging member for applying a force to the pavement to prevent uplifting:

said forward edge being substantially in alignment with ba Clltllng member having a leading edge spaced below one edge of said ground engaging member for performing and Offset from the ground engaglng Surfnce of 53rd Pave' an axial Cut in the pavement in cooperation with said mem engagimg membr for severmg a thickness of Pave' ground engaging member, and the second end being mm from 'ts foundauoni, spaced laterally away from Said ground engaging c. sai-d cutting member having a cutting edge immediately member, said blade extending rearwardly and upwardly l0 acl-laem an edge of Sald p avemelit engagmg member ex' from said forward edge with the portion of the blade exndmg. upwardly from Said leadmg eige so :is to coact with said pavement engaging member in forming a clean tending behind said first end rising more rapidly and to a i side cut in said pavement, and relatively greater elevation than the portion behind said d r l,

. l a rame to which said pavement engaging member and second .end threby causmg the pavement to be lifted .nd i5 cutting member are attached, said frame having means curled m a (ilrecuon awly from Sald ground engaging adapted for connection to a prime mover for continumember as sa@ apparatus 's mgl/ed forwardly' ously moving said device through asphaltic pavement for 2. A pavement slicer, cutter and lifter comprising: forming linear Cut therethrough. a device descnbed m lalm l and; 1il.A pavement cutter as described in claim 10 wherein: a similar second device as described in claim l laterally Said pavement engaging member is a wheel journaled on spaced from said first-named device wherein the inner Said frame for free rotation. edges )f ad pa" d gmund engaging members dene the l2. A pavement cutter as described in claim l0 wherein: outer h mts of the ldth Ofa trench' said pavement engaging member is pivotally mounted on said 3. A device as described in claim 2 wherein said frame is frame; adapted for demoumable Connection to an elevating member connection means formed in said frame for selectively enon Said Prlme mover and Sold ground .engaglng member s a gaging said pivoted ground engaging member at different wheel mounted substantially beneath said ripper bar. points for placin'g Said pavement engaging member and 4-Adevce as descrlbedm ClalmSWherem: the leading edge of said cutting member at different a. said frame consists ofa horizontal member demountably elevations so as lo sever different thicknesses of pave connected to said ripper bar; ment from the subgradeb. a vertical member integral with said horizontal member 13 A pavement cutter as described in claim 10 including:

extondlng downwardly from an end of Sold llorlzontal a starting point connected to said cutting member and exmernber rearwardly of Said Wheel; and tending downwardly and forwardly ofsaid leading edge so c. said blade being connected to said vertical member. that the pavement Will be Punctul-ed and the leading edge 5 Adel/loo as desorlbed ln Clalmilnollldlng 35 will drop to the selected elevation for performing its aa Wheel Carrying member PlVomlly attached to the leadoperation ofsevering the pavement from the subgrade.

lng end ofsald l'lorlzontal member; 14. A pavement cutting device as described in claim 10 inb. said wheel being attached to said wheel carrying member; cluding;

and an Outrigger ground engaging member spaced laterally from c. means connected to the trailing end of said wheel carry- 40 said cutting member opposite the placement of the firsting member biasing said wheel to the ground during named pavement engaging member for limiting laterally operation. the extent of the pavement breaking.

6. A device as described in claim 5 including: 15. A pavement cutting device as described in claim 14 a. an adjustment member pivotally connected to the trailing wherein:

end of said wheel carrying member in an upright manner, said first-named ground engaging member is mounted on a said adjustment member being formed with a plurality of pivot member which is moveable to a position laterally spaced openings; spaced from said cutting member on a side opposite said b. an upright retainer member connected to said frame havfirst-named Outrigger member so as to permit lateral ing an opening registerable with an opening of said adjustbreaking of said pavement in an unrestricted manner ment member; and between said Outrigger member and said first-named ci a pin member for registration in said above-named ground engaging member in the laterally disposed posiopenings for selectively adjusting the depth of said blade tion. in relation to the bottom edge of said wheel for determin- 16. A pavement Cutting device as described l.: r`laim 10 ining the thickness of the slice of the pavement to be cut Cluding and lifted a second pavement engaging member spaced from said first- 7 Adevice as described in claim 6 including; named ground engaging member with just sufficient a. a spring coaxially surrounding said adjustment member; distance l0 Place the Cutting member therebetween b. upper fixed spring retainer means connected to Said 17. .A pavement cutting device as described in claim 16 upright retainer; and Wlleroln c. lower floating spring retainer means having a cylindrical Sold ground ongaglng members are Wheels Connected to an member mounted coaxially within said spring and suraxle journaled on Said frame for fred rOIaOn; and l rounding said adjustable member and having an opening a gllldo member oxtendlng from Sald axle between Said therethrough for receiving said pin, and a horizontal /neels upwardly and rearwardly tro Prevent Severed Por member engaging the lOWer end of said spring. tions of pavement from traveling forwardly of said 8. A device as described in claim l wherein: Wlleel5- l l l a. said first end of said forward edge of said blade substanlt;- A cuttlng devlfre as descrlbed ln Clalm 16 Whereln tially leads said second end said ground engaging members are wheels connected to an 9 Ader/ice as described in clalrnswhereim axle journaled onsaid frame for free rotation and are the upper edge of Said bladc adjacent said ground engag dimensioned in width and in wheel diameter'to roll freely 7U on nonpaved surfaces with a minimum of disturbance to the surface. 

1. A pavement slicer, cutter and lifter comprising: a. a frame adapted for attachment to a prime mover; b. a ground engaging member mounted on said frame adapted for applying surface pressure against said ground over a substantially sufficient area to prevent pavement uplift lateral to the direction of movement of said device; and c. a compound curved blade mounted on said frame having a forward elongated edge positioned at a lower elevation relative to said ground engaging member for slicing a thickness of pavement from the subgrade, a first end of said forward edge being substantially in alignment with one edge of said ground engaging member for performing an axial cut in the pavement in cooperation with said ground engaging member, and the second end being spaced laterally away from said ground engaging member, said blade extending rearwardly and upwardly from said forward edge with the portion of the blade extending behind said first end rising more rapidly and to a relatively greater elevation than the portion behind said second end thereby causing the pavement to be lifted and curled in a direction away from said ground engaging member as said apparatus is moved forwardly.
 2. A pavement slicer, cutter and lifter comprising: a device described in claim 1 and; a similar second device as described in claim 1 laterally spaced from said first-named device wherein the inner edges of said pair of ground engaging members define the outer limits of the width of a trench.
 3. A device as described in claim 2 wherein said frame is adapted for demountable connection to an elevating member on said prime mover and said ground engaging member is a wheel mounted substantially beneath said ripper bar.
 4. A device as described in claim 3 wherein: a. said frame consists of a horizontal member demountably connected to said ripper bar; b. a vertical member integral with said horizontal member extending downwardly from an end of said horizontal member rearwardly of said wheel; and c. said blade being connected to said vertical member.
 5. A device as described in claim 4 including: a. a wheel carrying member pivotally attached to the leading end of said horizontal member; b. said wheel being attached to said wheel carrying member; and c. means connected to the trailing end of said wheel carrying member biasing said wheel to the ground during operation.
 6. A device as described in claim 5 including: a. an adjustment member pivotally connected to the trailinG end of said wheel carrying member in an upright manner, said adjustment member being formed with a plurality of spaced openings; b. an upright retainer member connected to said frame having an opening registerable with an opening of said adjustment member; and c. a pin member for registration in said above-named openings for selectively adjusting the depth of said blade in relation to the bottom edge of said wheel for determining the thickness of the slice of the pavement to be cut and lifted.
 7. A device as described in claim 6 including: a. a spring coaxially surrounding said adjustment member; b. upper fixed spring retainer means connected to said upright retainer; and c. lower floating spring retainer means having a cylindrical member mounted coaxially within said spring and surrounding said adjustable member and having an opening therethrough for receiving said pin, and a horizontal member engaging the lower end of said spring.
 8. A device as described in claim 1 wherein: a. said first end of said forward edge of said blade substantially leads said second end.
 9. A device as described in claim 8 wherein: a. the upper edge of said blade adjacent said ground engaging member is spaced laterally away from said ground engaging member and a portion of said upper end of said blade is positioned above the upper surface of said pavement to be lifted.
 10. A pavement cutting device comprising: a. a pavement engaging member for applying a force to the pavement to prevent uplifting: b. a cutting member having a leading edge spaced below and offset from the ground engaging surface of said pavement engaging member for severing a thickness of pavement from its foundation; c. said cutting member having a cutting edge immediately adjacent an edge of said pavement engaging member extending upwardly from said leading edge so as to coact with said pavement engaging member in forming a clean side cut in said pavement; and d. a frame to which said pavement engaging member and cutting member are attached, said frame having means adapted for connection to a prime mover for continuously moving said device through asphaltic pavement for forming a linear cut therethrough.
 11. A pavement cutter as described in claim 10 wherein: said pavement engaging member is a wheel journaled on said frame for free rotation.
 12. A pavement cutter as described in claim 10 wherein: said pavement engaging member is pivotally mounted on said frame; connection means formed in said frame for selectively engaging said pivoted ground engaging member at different points for placing said pavement engaging member and the leading edge of said cutting member at different elevations so as to sever different thicknesses of pavement from the subgrade.
 13. A pavement cutter as described in claim 10 including: a starting point connected to said cutting member and extending downwardly and forwardly of said leading edge so that the pavement will be punctured and the leading edge will drop to the selected elevation for performing its operation of severing the pavement from the subgrade.
 14. A pavement cutting device as described in claim 10 including: an outrigger ground engaging member spaced laterally from said cutting member opposite the placement of the first-named pavement engaging member for limiting laterally the extent of the pavement breaking.
 15. A pavement cutting device as described in claim 14 wherein: said first-named ground engaging member is mounted on a pivot member which is moveable to a position laterally spaced from said cutting member on a side opposite said first-named outrigger member so as to permit lateral breaking of said pavement in an unrestricted manner between said outrigger member and said firstnamed ground engaging member in the laterally disposed position.
 16. A pavement cutting device as described in claim 10 including: a second pavement engaging member spaced from said firsT-named ground engaging member with just sufficient distance to place the cutting member therebetween.
 17. A pavement cutting device as described in claim 16 wherein: said ground engaging members are wheels connected to an axle journaled on said frame for free rotation; and a guide member extending from said axle between said wheels upwardly and rearwardly to prevent severed portions of pavement from traveling forwardly of said wheels.
 18. A cutting device as described in claim 16 wherein: said ground engaging members are wheels connected to an axle journaled on said frame for free rotation and are dimensioned in width and in wheel diameter to roll freely on nonpaved surfaces with a minimum of disturbance to the surface.
 2. A pavement slicer, cutter and lifter comprising: a device described in claim 1 and; a similar second device as described in claim 1 laterally spaced from said first-named device wherein the inner edges of said pair of ground engaging members define the outer limits of the width of a trench.
 3. A device as described in claim 2 wherein said frame is adapted for demountable connection to an elevating member on said prime mover and said ground engaging member is a wheel mounted substantially beneath said ripper bar.
 4. A device as described in claim 3 wherein: a. said frame consists of a horizontal member demountably connected to said ripper bar; b. a vertical member integral with said horizontal member extending downwardly from an end of said horizontal member rearwardly of said wheel; and c. said blade being connected to said vertical member.
 5. A device as described in claim 4 including: a. a wheel carrying member pivotally attached to the leading end of said horizontal member; b. said wheel being attached to said wheel carrying member; and c. means connected to the trailing end of said wheel carrying member biasing said wheel to the ground during operation.
 6. A device as described in claim 5 including: a. an adjustment member pivotally connected to the trailinG end of said wheel carrying member in an upright manner, said adjustment member being formed with a plurality of spaced openings; b. an upright retainer member connected to said frame having an opening registerable with an opening of said adjustment member; and c. a pin member for registration in said above-named openings for selectively adjusting the depth of said blade in relation to the bottom edge of said wheel for determining the thickness of the slice of the pavement to be cut and lifted.
 7. A device as described in claim 6 including: a. a spring coaxially surrounding said adjustment member; b. upper fixed spring retainer means connected to said upright retainer; and c. lower floating spring retainer means having a cylindrical member mounted coaxially within said spring and surrounding said adjustable member and having an opening therethrough for receiving said pin, and a horizontal member engaging the lower end of said spring.
 8. A device as described in claim 1 wherein: a. said first end of said forward edge of said blade substantially leads said second end.
 9. A device as described in claim 8 wherein: a. the upper edge of said blade adjacent said ground engaging member is spaced laterally away from said ground engaging member and a portion of said upper end of said blade is positioned above the upper surface of said pavement to be lifted.
 10. A pavement cutting device comprising: a. a pavement engaging member for applying a force to the pavement to prevent uplifting: b. a cutting member having a leading edge spaced below and offset from the ground engaging surface of said pavement engaging member for severing a thickness of pavement from its foundation; c. said cutting member having a cutting edge immediately adjacent an edge of said pavement engaging member extending upwardly from said leading edge so as to coact with said pavement engaging member in forming a clean side cut in said pavement; and d. a frame to which said pavement engaging member and cutting member are attached, said frame having means adapted for connection to a prime mover for continuously moving said device through asphaltic pavement for forming a linear cut therethrough.
 11. A pavement cutter as described in claim 10 wherein: said pavement engaging member is a wheel journaled on said frame for free rotation.
 12. A pavement cutter as described in claim 10 wherein: said pavement engaging member is pivotally mounted on said frame; connection means formed in said frame for selectively engaging said pivoted ground engaging member at different points for placing said pavement engaging member and the leading edge of said cutting member at different elevations so as to sever different thicknesses of pavement from the subgrade.
 13. A pavement cutter as described in claim 10 including: a starting point connected to said cutting member and extending downwardly and forwardly of said leading edge so that the pavement will be punctured and the leading edge will drop to the selected elevation for performing its operation of severing the pavement from the subgrade.
 14. A pavement cutting device as described in claim 10 including: an outrigger ground engaging member spaced laterally from said cutting member opposite the placement of the first-named pavement engaging member for limiting laterally the extent of the pavement breaking.
 15. A pavement cutting device as described in claim 14 wherein: said first-named ground engaging member is mounted on a pivot member which is moveable to a position laterally spaced from said cutting member on a side opposite said first-named outrigger member so as to permit lateral breaking of said pavement in an unrestricted manner between said outrigger member and said first-named ground engaging member in the laterally disposed position.
 16. A pavement cutting device as described in claim 10 including: a second pavement engaging member spaced from said firsT-named ground engaging member with just sufficient distance to place the cutting member therebetween.
 17. A pavement cutting device as described in claim 16 wherein: said ground engaging members are wheels connected to an axle journaled on said frame for free rotation; and a guide member extending from said axle between said wheels upwardly and rearwardly to prevent severed portions of pavement from traveling forwardly of said wheels.
 18. A cutting device as described in claim 16 wherein: said ground engaging members are wheels connected to an axle journaled on said frame for free rotation and are dimensioned in width and in wheel diameter to roll freely on nonpaved surfaces with a minimum of disturbance to the surface. 